WO2010054731A1

WO2010054731A1 - Materials for organic electroluminescent devices

Info

Publication number: WO2010054731A1
Application number: PCT/EP2009/007407
Authority: WO
Inventors: Amir Hossain Parham; Arne Buesing; Anja Gerhard; Joachim Kaiser; Rocco Fortte
Original assignee: Merck Patent Gmbh
Priority date: 2008-11-13
Filing date: 2009-10-15
Publication date: 2010-05-20
Also published as: JP2012508700A; CN102076816A; TW201024311A; KR101704825B1; KR20110095130A; JP5774487B2; CN102076816B; DE102008057050B4; US8597798B2; US20110095281A1; EP2344608A1; DE102008057050A1

Abstract

The present invention relates to transition metal complexes of the general formulae (I) or (II), in particular as emitter molecules in organic electronic devices, a layer and an electronic device which contain the compounds according to the invention as well as a method for producing the compounds according to the invention.

Description

Materials for organic electroluminescent devices

The present invention relates to transition metal complexes of the general formulas I or II, in particular as emitter molecules in organic electronic devices, to a layer and to an electronic device which contain the compounds according to the invention, and to a process for preparing the compounds according to the invention.

Chelate complexes and organometallic compounds are used as functional materials in a number of different applications, which can be attributed to the electronics industry in the broadest sense. In the case of the organic electroluminescent devices based on organic components (general description of the structure, cf., US Pat. Nos. 4,539,507 and 5,151,629) or their individual components, the organic light-emitting diodes (OLEDs), the market introduction has already taken place. Despite the successes already achieved, further improvements are desirable here.

In recent years, organometallic complexes which exhibit phosphorescence rather than fluorescence are increasingly being discussed (M.A. Baldo, S. Lamansky, P.E. Burrows, M.E. Thompson, S.R. Forrest, Appl. Phys. Lett., 1999, 75, 4-6). For theoretical spin-statistical reasons, up to fourfold energy and power efficiency is possible using organometallic compounds as phosphorescence emitters. As essential conditions for the practical application here are in particular a high operating life, a high stability against temperature load and a low application and operating voltage to enable mobile applications to call.

In addition to the individual weak points specific to each material, the class of known metal complexes has a general need for improvement, which is briefly outlined below: Many of the known metal complexes have low thermal stability (see: RG Charles, J. Inorg., Nucl. Chem., 1963, 25, 45). In the case of vacuum deposition, this inevitably always leads to the release of organic pyrolysis products, which in some cases considerably reduce the operational lifetime of OLEDs even in small quantities.

• Likewise, the strong interaction of the complex units in the solid, especially in planar complexes of d ⁸ metals such as platinum (II), the aggregation of the complex units in the emitter layer, if the doping level exceeds about 0.1%, which is the case according to the current state of the art is. Upon excitation (optically or electrically), this aggregation leads to the formation of so-called excimers or exciplexes. These aggregates often have an unstructured broad emission band, which makes the generation of pure primary colors (RGB) considerably more difficult or completely impossible. As a rule, the efficiency for this transition also decreases.

• It also emerges from the above that the emission color depends strongly on the degree of doping, a parameter which can be precisely controlled only with considerable technical effort, especially in large production plants.

Metal complexes of the transition metals of group 10 (Ni, Pd, Pt), in which the central metal has two aromatic N and two C atoms (WO 2004/108857, WO 2005/042550 , WO 2005/042444, US 2006/0134461 A1) or two imine-like N atoms in combination with two phenolic O atoms (WO 2004/108857) or via two aromatic N and two basic N atoms (WO 2004/108857) is bound. The known compounds have, inter alia, electroluminescence in the blue, red and green regions of the electromagnetic spectrum.

Nevertheless, there is still a need for further compounds which do not have the abovementioned disadvantages and which are preferably in the blue, red and green range of the electrochemical show magnetic spectrum electroluminescence and in particular can be used in substance as a light-emitting layer.

The object of the invention was thus to provide such compounds.

Surprisingly, it has been found that by metal complexes with imine-like N atoms in combination with aromatic C atoms or olefinic C atoms in combination with aromatic N atoms as phosphorescence emitters in OLEDs a high operational lifetime and by bridging these ligands a high stability to thermal stress and a low operating and operating voltage can be achieved.

The present invention provides a compound of general formula I.

Formula ready, where

M is a metal ion of oxidation state +2,

Ar is the same or different at each occurrence an aromatic or heteroaromatic ring system which may be substituted by one or more arbitrary radicals R and the ring systems Ar may optionally be linked together by single bonds or any radicals R, Y is the same or different at every occurrence C ₁ N or P, with the proviso that always two C atoms and two N atoms or always two C atoms and two P atoms are bound to the metal,

R ^{1 is} any residue.

The present invention further provides a compound of general formula II

Formula Il

ready, being

M is a metal ion of oxidation state +2,

Ar is the same or different at each occurrence an aromatic or heteroaromatic ring system which may be substituted by one or more arbitrary radicals R and the ring systems Ar may optionally be linked together by single bonds or any radicals R,

Y is the same or different at each occurrence C, N or P, with the proviso that always two C atoms and two N atoms or always two C atoms and two P atoms are bound to the metal,

R ^{1 is} any residue. In a preferred embodiment of the invention is in the compounds of general formula I or II

R is the same or different at each occurrence H, D, F ₁ Cl, Br ₁ I ₁ N (Ar ¹ ) ₂ , N (R ² ) ₂ , CN, NO ₂ , Si (R ² ) ₃ , B (OR ² ) ₂ , C (= O) Ar ¹ , C (= O) R ² , P (= O) (Ar ¹ ) _2l P (= O) (R ² ) ₂ , S (= O) Ar ¹ , S (= O) R ² , S (= O) ₂ Ar ¹ , S (= O) ₂ R ² , -CR ² = CR ² Ar \ OSO ₂ R ² , a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 ° C Atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 carbon atoms, each of which may be substituted by one or more radicals R ² , wherein one or more non-adjacent CH ₂ groups represented by R ² C = CR ² , C≡C, Si (R ² ) _2l Ge (R ² ) ₂ , Sn (R ² ) ₂ , C = O, C = S, C = Se, C = NR ² , P (= O) (R ² ), SO, SO ₂ , NR ² , O, S or CONR ² may be replaced and wherein one or more H atoms may be replaced by D, F, Cl ₁ Br, I, CN or NO ₂ , or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, each of which may be substituted by one or more radicals R ² , or a Aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms which may be substituted by one or more radicals R ² , or a combination of these systems, where two or more substituents R may also together form a mono- or polycyclic, aliphatic or aromatic ring system,

Ar ^{1 is} identical or different at each occurrence, an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, which may be substituted by one or more non-aromatic radicals R,

R ^{1 is the} same or different at each occurrence H, D, F, CF ₃ , CN, a

Alkyl, alkoxy or thioalkoxy group having 1 to 40 carbon atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having from 3 to 40 carbon atoms, each of which may be substituted with one or more R ² groups, wherein one or more non-adjacent CH ₂ groups is represented by R ² C = CR ² , C ≡C, Si (R ² ) ₂ , Ge (R ² ) ₂ , Sn (R ² ) ₂ , and wherein one or more H atoms are represented by D, F, Cl, Br,

I, CN or NO ₂ may be replaced, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, each of which may be substituted by one or more radicals R ² , or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, the may be substituted by one or more radicals R ² , or a combination of these systems, wherein R ^{1 may} also form with R a mono- or polycyclic, aliphatic or aromatic ring system,

R ^{2 is} identical or different at each occurrence H, D, F, CN or an aliphatic, aromatic and / or heteroaromatic hydrocarbon radical having 1 to 20 carbon atoms, in which also one or more H atoms may be replaced by F, where two or more substituents R ² also together form a mono- or polycyclic, aliphatic or aromatic ring system.

In a further preferred embodiment of the invention, M is Pd or equal to Pt. More preferably, M is Pt.

In yet another preferred embodiment of the invention is in the compounds of general formula I or II

M Pt,

Ar is identical or different at each occurrence, an aromatic or heteroaromatic ring system having 5 to 10 aromatic ring atoms, which may be substituted by a plurality of radicals R,

Y is identical or different at each occurrence C or N, with the proviso that always two C atoms and two N atoms are bound to the metal, R is identical or different at each occurrence H, N (Ar ¹ J ₂ , CN, a straight-chain alkyl group having 1 to 10 C atoms, or an aromatic or heteroaromatic ring system having 5 to 15 aromatic ring atoms, each by one or more

Radicals R ² may be substituted,

R ^{1 is the} same or different at each occurrence H, D, CN, a

Alkyl group having 1 to 3 carbon atoms, or an aromatic or heteroaromatic ring system having 5 to 10 aromatic ring atoms, each of which may be substituted by one or more radicals R ² ,

R ^{2 is} identical or different in each occurrence, is H, F, CN or an aliphatic, aromatic and / or heteroaromatic hydrocarbon radical having 1 to 20 C atoms, where two or more

Substituents R ^{2 can} also form a mono- or polycyclic, aliphatic or aromatic ring system with each other; and

Ar ¹ is as defined above.

If the above-defined radicals occur several times within a compound, the radicals independently of one another on each occurrence can be the same or different, as defined.

The following general definitions also apply within this invention:

An aryl group in the sense of this invention contains 6 to 60 C atoms; a heteroaryl group in the context of this invention contains 2 to 60 carbon atoms and at least one heteroatom, with the proviso that the sum of

C atoms and heteroatoms at least 5 yields. The heteroatoms are preferably selected from N, O and / or S. Here, under an aryl group or heteroaryl either a simple aromatic cycle, ie benzene, or a simple heteroaromatic cycle, for example pyridine, pyrimidine, thiophene, etc., or a condensed (fused) aryl or heteroaryl group, for example, naphthalene, anthracene, phenanthrene, quinoline, isoquinoline, carbazole, etc., understood.

Particularly preferred for the purposes of this invention is the group Ar in the general formulas I or II benzene, naphthalene, pyridine, pyrimidine,

Pyrazine, pyridazine, quinoline, isoquinoline, furan, thiophene, pyrrole, benzofuran, benzothiophene and indole, most preferably benzene, naphthalene, pyridine, quinoline and isoquinoline.

An aromatic ring system in the sense of this invention contains 6 to 60 carbon atoms in the ring system. A heteroaromatic ring system in the sense of this invention contains 2 to 60 C atoms and at least one heteroatom in the ring system, with the proviso that the sum of C atoms and heteroatoms gives at least 5. The heteroatoms are preferably selected from N, O and / or S. An aromatic or heteroaromatic ring system in the sense of this invention is to be understood as meaning a system which does not necessarily contain only aryl or heteroaryl groups but in which also several aryl or heteroaryl groups Heteroaryl groups by a non-aromatic unit (preferably less than 10% of the atoms other than H), such as. As an sp ³ -hybridized C, N or O atom, may be interrupted. For example, systems such as 9,9'-spirobifluorene, 9,9-diarylfluorene, triarylamine, diaryl ethers, stilbene, etc. are to be understood as aromatic ring systems in the context of this invention, and also systems in which two or more aryl groups, for example by a linear or cyclic alkyl group or interrupted by a silyl group.

An aromatic or heteroaromatic ring system having 5-60 aromatic ring atoms, which may be substituted in each case by the abovementioned radicals R ¹ and which may be linked via any position on the aromatic or heteroaromatic compounds, is understood in particular to mean groups derived from benzene , Naphthalene, anthracene, benzanthracene, phenanthrene, pyrene, chrysene, perylene, fluoranthene, naphthacene, pentacene, benzpyrene, biphenyl, biphenylene, terphenyl, terphenylene, fluorene, spirobifluorene,

Dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis- or trans- Indenofluorene, truxene, isotruxene, spirotruxene, spiroisotruxene, furan, benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole, indole, isoindole, carbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6- quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline, phenothiazine, phenoxazine,

Pyrazole, indazole, imidazole, benzimidazole, naphthimidazole, phenanthrimidazole, pyridimidazole, pyrazine imidazole, quinoxaline imidazole, oxazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1, 2-thiazole, 1, 3-thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine, Benzpyrimidine, quinoxaline, 1,5-diazaanthracene, 2,7-diazapyrene, 2,3-diazapyrene, 1, 6-diazapyrene, 1, 8-diazapyrene, 4,5-diazapyrene, 4,5,9,10-tetraazaperylene, Pyrazine, phenazine, phenoxazine, phenothiazine, fluorubin, naphthyridine, azacarbazole, benzocarboline, phenanthroline, 1, 2,3-triazole, 1, 2,4-triazole, benzotriazole, 1, 2,3-oxadiazole, 1, 2,4- Oxadiazole, 1, 2,5-oxadiazole, 1, 3,4-oxadiazole, 1, 2,3-thiadiazole, 1, 2,4-thiadiazole, 1, 2,5-thiadiazole, 1, 3,4-thiadiazole, 1, 3,5-triazine, 1, 2,4-triazine, 1, 2,3-triazine, tetrazole, 1, 2,4,5-tetrazine, 1, 2,3,4-tetrazine, 1, 2, 3,5-tetrazine, purine, pteridine, indolizine and benzothiadiazole.

In the context of the present invention, an aliphatic hydrocarbon radical or an alkyl group which may typically contain from 1 to 40 or also from 1 to 20 carbon atoms, and in which also individual H atoms or Ch.sup.1 - groups are substituted by the abovementioned groups prefers the radicals methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl, s-pentyl, cyclopentyl, n- Hexyl, cyclohexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, ethenyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, Octenyl, cyclooctenyl, ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl or octynyl understood. Among an alkoxy group having 1 to 40 carbon atoms, methoxy, trifluoromethoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, n-pentoxy, s-pentoxy, 2-methylbutoxy, n-hexoxy, cyclohexyloxy, n-heptoxy, cycloheptyloxy, n-octyloxy, cyclooctyloxy, 2-ethylhexyloxy, pentafluoroethoxy and 2,2,2-trifluoroethoxy understood. Among a thioalkyl group having 1 to 40 carbon atoms, in particular methylthio, ethylthio, n-propylthio, i-propylthio, n-butylthio, i-butylthio, s-butylthio, t-butylthio, n-pentylthio, s-pentylthio, n-hexylthio, cyclohexylthio, n-heptylthio, cycloheptylthio, n-octylthio, cyclooctylthio, 2-ethylhexylthio, Trifluoromethylthio, pentafluoroethylthio, 2,2,2-trifluoroethylthio, ethenylthio, propenylthio, butenylthio, pentenylthio, cyclopentenylthio, hexenylthio, cyclohexenylthio, heptenylthio, cycloheptenylthio, octenylthio, cyclooctenylthio, ethynylthio, propynylthio, butynylthio, pentynylthio, hexynylthio, Heptynylthio or octynylthio. In general, alkyl, alkoxy or thioalkyl groups according to the present invention may be straight-chain, branched or cyclic, wherein one or more non-adjacent CH ₂ groups are represented by R ¹ C = CR ¹ , C≡C, Si (R ¹ ) ₂ , Ge (R ¹ ) ₂ , Sn (R ¹ ) ₂ , C = O, C = S, C = Se, C = NR ¹ , P (O) (R ¹ ), SO, SO ₂ , NR ¹ , O, S or CONR ¹ can be replaced; Furthermore, one or more H atoms can also be replaced by F, Cl, Br, I, CN or NO ₂ , preferably F, Cl or CN, more preferably F or Cl, particularly preferably F.

A preferred embodiment of the compounds according to the formulas I and II are the compounds according to one of the following formulas IM to IV,

Formula IM Formula IV

wherein M, Y, R and R ^{1 have} the abovementioned meaning and X is CR or N. In this case, preferably a maximum of two symbols X, more preferably at most one symbol X per cycle for N, and the other symbols X in this cycle stand for CR. Most preferably, all groups X are in one cycle for CR. Particularly preferred embodiments of the abovementioned compounds are the compounds of the following formulas V to XVI:

Formula VIII Formula IX Formula X

Formula XI Forms I XIII Forms XIII

Formula XV Formula XVI

Formula XIV

where the symbols used have the meanings given above.

In addition to the preferred compounds mentioned above, particular preference is furthermore given to the compounds shown in Table 1 below:

Table 1: Examples of compounds of the invention according to the formulas I to XVI

45 46

47 48

49 50

51 52

53 54

-I9¬

75 76

77 78

79 80

81 82

83 84

85 86

87 88

89 90

91 92

93 94

95 96

The compounds according to the invention are preferably square-planar complexes or approximately square-planar complexes which contain a four-coordinate metal ion in the oxidation state +2. The metal is preferably selected from metals of the tenth group of the Periodic Table of the Elements, in particular Pd and Pt. The compounds of the invention have a triplet emission and have a very good life, high efficiency, high stability to thermal stress and a high glass transition temperature Tg.

The invention also provides a process for the preparation of a compound of general formula I or II

Formula I formula

wherein M, Y, Ar, R, R ¹ and R ^{2 have} the meaning defined above. The compounds according to the invention of the formula I or II can be prepared by synthesis steps which are generally known to the person skilled in the art.

As a starting point for the ligand synthesis z. B. 6-phenyl-pyridine-2-carboxaldehyde (J.Am.Chem.Soc., 2003, 125 (8), 2113-2128), 2-biphenylamine (Tetrahedron Lett., 2008, 49 (9), 1555-1558). , 3-pyridin-2-yl-benzaldehyde (Org. Lett. 2004, 6 (19), 3337-3340) or 2-chloro-8-nitroquinoline (Australian J. Chem. 2003, 56 (1), 39 -44).

In a first stage, the synthesis of the corresponding partial ligands takes place, which are combined in a further step to form the desired ligand system. Subsequently, a reaction with the corresponding metal (for example, Pt or Pd), which is usually used as a solution of a suitable metal salt, for example K ₂ PtCl ₄ or K ₂ PdCl ₄ , is used.

A general procedure for the preparation of the metal complexes according to formula I or II is shown in Schemes 1 to 4. The central metal Pt can be replaced by Pd in analogous reactions.

Scheme 1

C or C or

N Scheme 2

= N or = C or

= N

Totuol

X "= C or X" = C or X "= N

Scheme 4

'Cr °

THF / tBuOK Wittig

K ₂ RCI ₄ X = C and X ¹ = N and X "= N or X = N and X ¹ = N and X" = C or X = N and X "= C and X" = N

The invention also relates to the use of the compounds according to the invention in an organic electronic device. As organic electronic device according to the invention organic electroluminescent devices (OLEDs) or polymeric electroluminescent devices (PLEDs), organic integrated

Circuits (O-ICs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic solar cells (O-SCs), organic optical detectors, organic photoreceptors , organic FeId quench devices (O-FQDs), light-emitting electrochemical cells (LECs) or organic laser diodes (O-lasers), but in particular organic electroluminescent devices (= organic light-emitting diodes, OLEDs, PLEDs) are used.

The invention particularly relates to the use of the compounds according to the invention as emitter compound and / or as charge transport material and / or charge injection material, preferably in a corresponding layer. These can be either hole transport layers, hole injection layers, electron transport layers or electron injection layers. The use as a charge blocking material, depending on the structure, possible.

Likewise provided by the invention are organic electronic devices, such as. B. organic electroluminescent devices or polymeric electroluminescent devices (OLED, PLED), organic integrated circuits (O-ICs), organic field effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs) , organic solar cells (O-SCs), organic optical detectors, organic photoreceptors, organic field quench devices (O-FQDs), light-emitting electrochemical

Cells (LECs) or organic laser diodes (O-lasers), but in particular organic electroluminescent devices (= organic light-emitting diodes, OLEDs, PLEDs) containing one or more compounds according to formula I or II, as defined above. An organic electronic device in the sense of this invention is understood to mean an electronic device comprising anode, cathode and at least one layer, which contains at least one organic material. In this case, the device may also contain inorganic materials in addition to the organic material.

Preferably, the compound of formula I or II is in the electronic

Device within a layer.

The invention thus also provides a layer containing a compound of the formula I or II, as defined above.

The organic electroluminescent device includes cathode, anode and at least one emitting layer. In addition to these layers, they may also contain further layers, for example one or more hole injection layers, hole transport layers, hole blocking layers, electron transport layers, electron injection layers, exciton blocking layers and / or charge generation layers (Charge Generation Layers, IDMC 2003, Taiwan, Session 21 OLED (5), T. Matsumoto, T. Nakada, J. Endo, K. Mori, N. Kawamura, A. Yokoi, J. Kido, Multiphoton Organic EL Device Having Charge Generation Layer). Likewise, interlayer can be introduced between two emitting layers, which have, for example, an exciton-blocking function. It should be noted, however, that not necessarily each of these layers must be present. These layers may contain compounds of general formula I or II as defined above.

In a preferred embodiment of the invention, the compound according to formula I or II is used as the emitting compound in an emitting layer or as a charge transport compound. In this case, the organic electroluminescent device may contain an emitting layer, or it may contain a plurality of emitting layers, wherein at least one emitting layer contains at least one compound according to formula I or II, as defined above. If several emission layers are present, they preferably have a total of several emission maxima between 380 nm and 750 nm, so that overall white emission results, ie, in the emitting layers uses different emitting compounds that can fluoresce or phosphoresce. Particular preference is given to three-layer systems, the three layers exhibiting blue, green and orange or red emission (for the basic structure see, for example, WO 05/011013).

When the compound according to formula I or II is used as the emitting compound in an emitting layer, it is preferably used in combination with one or more compounds acting as a matrix. The mixture of the compound according to formula I or II and the matrix material in these cases contains between 1 and 99% by weight, preferably between 2 and 90% by weight, more preferably between 3 and 40% by weight, in particular between 5 and 15 wt .-% of the compound according to formula I or II based on the total mixture of emitter and matrix material. Accordingly, the mixture contains between 99 and 1 wt .-%, preferably between 98 and 10 wt .-%, particularly preferably between 97 and 60 wt .-%, in particular between 95 and 85 wt .-% of the matrix material based on the total mixture of Emitter and matrix material.

Preferred matrix materials are aromatic ketones, aromatic phosphine oxides or aromatic sulfoxides or sulfones, e.g. B. according to WO 04/013080, WO 04/093207, WO 06/005627 or the non-disclosed application DE 102008033943.1, triarylamines, carbazole derivatives, z. B. CBP (N, N-Biscarbazolylbiphenyl) or in WO 05/039246, US 2005/0069729, JP 2004/288381, EP 1205527 or

WO 08/086851 disclosed carbazole derivatives, indolocarbazole derivatives, e.g. B. according to WO 07/063754 or WO 08/056746, Azacarbazolderivate, z. B. according to EP 1617710, EP 1617711, EP 1731584, JP 2005/347160, bipolar matrix materials, for. B. according to WO 07/137725, silanes, z. B. according to WO 05/111172, azaborole or boronic esters, for. B. according to WO 06/117052, triazine derivatives, z. B. according to the unpublished application DE 102008036982.9, WO 07/063754 or WO 08/056746, zinc complexes, for. B. according to EP 652273 or WO 09/062578, or diazasilol or tetraazasilol derivatives, z. B. according to the unpublished application DE 102008056688.8. Another preferred embodiment of the invention is the use of the compound according to formula I or II as emitter material in combination with two or more different matrix materials. Suitable matrix materials in these cases are those mentioned above

Links.

Further preferred is an organic electroluminescent device wherein one or more layers are coated by a sublimation method. The materials in vacuum sublimation at a pressure of less than 10 10 ^"6 ⁷ mbar ^{~ 5} mbar, preferably less than mbar, particularly preferably less than 10 ^'by vapor deposition.

Also preferred is an organic electroluminescent device, characterized in that one or more layers with the

OVPD (Organic Vapor Phase Deposition) process or coated by means of a carrier gas sublimation. The materials are applied at a pressure between 10 ^{"applied 5} mbar and 1 bar. A special case of this method is the OVJP (organic vapor jet printing) method in which the materials are applied directly through a nozzle and patterned (eg. BMS Arnold et al., Appl. Phys. Lett., 2008, 92, 053301).

Further preferred is an organic electroluminescent device, characterized in that one or more layers of solution, such. B. by spin coating, or with any printing process, such. As screen printing, flexographic printing or offset printing, but more preferably LITI (Light Induced Thermal Imaging, thermal transfer printing) or inkjet printing (ink jet printing), are produced. For this purpose, soluble compounds are necessary, which are optionally obtained by suitable substitution.

These methods are generally known to the person skilled in the art and can be applied by him without problems to organic electroluminescent devices comprising compounds of the formula I or II as defined above. The compounds according to the invention described above, in particular compounds which are substituted or functionalized with reactive groups, can be used as monomers for producing corresponding oligomers, dendrimers or polymers.

Another object of the invention are therefore oligomers, polymers or dendrimers containing one or more compounds of formula I or II, as defined above, wherein one or more bonds of the compounds of formula I or II to the polymer, oligomer or

Dendrimer are present. Depending on the linkage of the compound according to formula I or II, the complex therefore forms a side chain of the oligomer or polymer or is linked in the main chain. The polymers, oligomers or dendrimers may be conjugated, partially conjugated or non-conjugated. The oligomers or polymers may be linear, branched or dendritic.

To prepare the oligomers or polymers, the functionalized compounds of the formulas I or II are homopolymerized or copolymerized with further monomers. Preferred are copolymers, wherein the

Compounds according to formula I or II to 0.01 to 50 mol%, particularly preferably in the range of 0.1 to 20 mol% are present. Suitable and preferred comonomers which form the polymer backbone are selected from fluorenes (eg according to EP 842208 or WO 00/22026), spirobifluorenes (for example according to EP 707020, EP 894107 or US Pat

WO 06/061181), para-phenylenes (for example according to WO 92/18552), carbazoles (for example according to WO 04/070772 or WO 04/113468), thiophenes (for example according to EP 1028136), Dihydrophenanthrenes (eg according to WO 05/014689), cis- and trans-indenofluorenes (eg according to WO 04/041901 or WO 04/113412), ketones (for example according to US Pat

WO 05/040302), phenanthrenes (for example according to WO 05/104264 or WO 07/017066) or else several of these units. The proportion of these units in total is preferably in the range of at least 50 mol%. The polymers, oligomers and dendrimers may also contain other units, for example hole transport units, in particular those based on triarylamines, and / or electron transport units. Polymers containing compounds of general formula I or II can be used for the production of PLEDs, in particular as emitter layer in PLEDs. The production of a polymeric emitter layer can be achieved, for example, by coating from solution (spin-coating or

Printing process).

The compounds according to the invention and the organic electroluminescent devices produced therewith have the following surprising advantages over the prior art:

In contrast to many metal complexes according to the prior art which undergo partial or complete pyrolytic decomposition on sublimation, the compounds according to the invention have a high thermal stability.

• By using bulky substituents on the aromatic or heteroaromatic ring systems, the aggregation of the complexes and thus the formation of excimers or exciplexes can be largely suppressed.

Organic electroluminescent devices containing compounds according to formula I or II as emitting materials have an excellent lifetime.

Blue, red and green phosphorescent complexes are available which have an efficient deep blue, red or even green emission color and have a long lifetime when used in organic electroluminescent devices. This is a significant advance over the prior art as previously blue, red and green phosphorescent devices were often accessible with poor color coordinates and, in particular, poor life. The compounds according to the invention, used in organic electroluminescent devices, lead to high efficiencies and steep current-voltage curves at low threshold voltages.

These advantages mentioned above are not accompanied by a deterioration of the other electronic properties.

The invention is explained in more detail by the following examples without wishing to restrict them thereby. The person skilled in the art can synthesize further compounds according to the invention without inventive step and use these in organic electroluminescent devices.

EXAMPLES Unless stated otherwise, the following syntheses are carried out under an inert gas atmosphere in dried solvents. As starting materials serve z. 6-phenylpyridine-2-carboxaldehyde (J.Am.Chem.Soc., 2003, 125 (8), 2113-2128), 2-biphenylamine (Tetrahedron Lett., 2008, 49 (9), 1555-1558). , 3-pyridin-2-ylbenzaldehyde (Org. Lett. 2004, 6 (19), 3337-3340), 2-chloro-8-nitroquinoline (Australian J. Chem. 2003, 56 (1), 39-44).

Example 1 Synthesis Protocol for Metal Complex (1)

1st stage: ligand synthesis

The ligand synthesis is carried out using azeotropic distillation to carry out the water formed. First, 300 ml of dried toluene in a distillation apparatus in 500 ml Three-necked flask with stirrer, internal thermometer and dropping funnel heated to boiling. Subsequently, a solution of 20 g (120 mmol) of 2-biphenylamine in 50 ml of dried toluene and a solution of 21.9 g (120 mmol) of 6-phenylpyridine-2-carboxaldehyde in 50 ml of toluene are slowly added dropwise. The mixture is treated with catalytic amounts of p-toluenesulfonic acid. The distillation is carried out until the appearance of the clear condensed toluene. The residues of the solvent are removed in an oil pump vacuum (130 Pa). The ligand is recrystallized from toluene and washed with MeOH. This gives 31.5 g (94 mmol) of crystalline solid. The total yield is 80%.

2nd stage: complex synthesis:

To a solution of 17.2 g K ₂ PtCU (41.5 mmol) in 1300 ml of acetic acid is added under N _2, a solution of 13.8 g (41.5 mmol) of imine ligand in 1300 ml of acetic acid and stirred for 3 days at 90 ⁰ C. Nach 72 h, the precipitated solid is washed with cold methanol, dried in vacuo and then recrystallized under protective gas in EtOH _abs . This gives 15.9 g (30 mmol) of crystalline solid. The total yield is 73%.

Example 2 Synthesis Protocol for Metal Complex (8)

1st stage: ligand synthesis

The ligand synthesis is carried out using azeotropic distillation to carry out the water formed. First, 300 ml of dried toluene are heated to boiling in a distillation apparatus in a 500 ml three-necked flask with stirrer, internal thermometer and dropping funnel. Subsequently, a solution of 20 g (120 mmol) 2-biphenylamine in 50 ml of dried toluene and a solution of 21.9 g (120 mmol) of 3-pyridin-2-yl-benzaldehyde in 50 ml of toluene was added dropwise slowly. The mixture is treated with catalytic amounts of p-toluenesulfonic acid. The distillation is carried out until the appearance of the clear condensed toluene. The residues of the solvent are removed in an oil pump vacuum (130 Pa). The ligand is recrystallized from toluene and washed with MeOH. This gives 30.1 g (90 mmol) of crystalline solid. The total yield is 76%.

2nd stage: complex synthesis

To a solution of 17.2 g K ₂ PtCl ₄ (41.5 mmol) in 1300 ml of acetic acid is added under N _2, a solution of 13.8 g (41.5 mmol) of imine ligand in 1300 ml of acetic acid and stirred for 3 days at 90 ⁰ C. Nach 72 h, the precipitated solid is washed with cold methanol, dried in vacuo and then recrystallized under protective gas in EtOH _a b _s . This gives 14.3 g (27 mmol) of crystalline solid. The total yield is 66%.

Example 3 Synthesis Protocol for Metal Complex (30)

1st stage: 8-nitro-2-naphthyl-quinoline

18.9 g (110.0 mmol) of 1-naphthylboronic acid, 22.9 g (110.0 mmol) of 2-chloro-8-nitroquinoline and 44.6 g (210.0 mmol) of tripotassium phosphate are suspended in 500 ml of toluene, 500 ml of dioxane and 500 ml of water. To this suspension 913 mg (3.0 mmol) of tri-o-tolylphosphine and then Added 112 mg (0.5 mmol) of palladium (II) acetate and the reaction mixture heated under reflux for 16 h. After cooling, the organic phase is separated off, filtered through silica gel, washed three times with 200 ml of water and then concentrated to dryness. The yield is 26.4 g (87 mmol), corresponding to 80% of theory.

2nd stage: 8-amine-2-naphthyl-quinoline

12.6 g (42 mmol) of 8-nitro-2-naphthylquinoline and 1.99 g of Pd / C (10%) are suspended in 200 ml of methanol. While stirring at 0 ^° C., 8.4 g (222 mmol) of sodium borohydride are added in portions. After 2 h

Stirring, the clear solution is neutralized with dilute HCl. Thereafter, the solvent is removed, the resulting residue is washed thoroughly with water and recrystallized in dioxane. The precipitate is filtered and dried in vacuo. This gives 9.9 g (56.9 mmol) of crystalline solid. The total yield is 88%.

3rd stage: 1 - [(£) -8-quinolinylimino) methyl] naphthalene

The ligand synthesis is carried out using azeotropic distillation to carry out the water formed. First, 300 ml of dried toluene in a distillation apparatus in 500 ml

Three-necked flask with stirrer, internal thermometer and dropping funnel heated to boiling. Subsequently, a solution of 32.4 g (120 mmol) of 8-amine-2-naphthyl-quinoline in 50 ml of dried toluene and a solution of 12.7 g (120 mmol) of benzaldehyde in 50 ml of toluene are slowly added dropwise. The mixture is treated with catalytic amounts of p-toluenesulfonic acid. The distillation is carried out until the appearance of the clear condensed toluene. The residues of the solvent are removed in an oil pump vacuum (130 Pa). The ligand is recrystallized from toluene and washed with MeOH. This gives 32.1 g (89 mmol) of crystalline solid. The total yield is 75%.

4th stage: complex synthesis

To a solution of 17.2 g K ₂ PtCl ₄ (41.5 mmol) in 1300 ml of acetic acid is added under N _2, a solution of 14.8 g (41.5 mmol) of imine ligand in 1300 ml of acetic acid and stirred for 3 days at 90 ⁰ C. Nach 72 h, the precipitated solid is washed with cold methanol, in vacuo dried and then recrystallized under protective gas in EtOH _from s. This gives 13.4 g (24 mmol) of crystalline solid. The total yield is 59%.

Example 4: Preparation and Characterization of Organic

electroluminescent

Electroluminescent devices according to the invention can be prepared as described, for example, in WO 05/003253. Here the results of different OLEDs are compared. The basic structure, the materials used, the degree of doping and their layer thicknesses are identical for better comparability. The first device example describes a comparison standard according to the prior art in which the emission layer consists of the host material spiro-ketone and the guest material (dopant) Ir (piq) ₃ or a compound according to the invention. Furthermore, OLEDs of various constructions are described, in each case the host material is spiro ketone. Analogously to the above-mentioned general method, OLEDs are produced with the following structure:

Hole injection layer (HIL) 20 nm 2.2 ^I , 7,7'-tetrakis (di-para-tolylamino) spiro-9,9'-bifluorene

Hole transport layer (HTL) 20 nm NPB (N-naphthyl-N-phenyl-4,4 ¹ -diaminobiphenyl)

Emission layer (EML) 40 nm Host: spiro-ketone (SK) (bis (9,9 ^'- spirobifluorene-2-yl) ketone) dopant: Ir (piq) ₃ (10% doping, vapor-deposited; synthesized according to WO 03/0068526 ) or compounds of the invention

Electron conductor (ETL) 20 nm AlQ ₃

(Tris (quinolinato) aluminum (III).

Cathode 1 nm LiF, then 150 nm Al.

The structures of Ir (piq) ₃ and spiro-ketone are shown in the following for the sake of clarity:

lr (piq) ₃ spiro-ketone

The compounds according to the invention are shown below:

Example 1 Example 3

These not yet optimized OLEDs are characterized by default; For this purpose, the electroluminescence spectra, the efficiency (measured in cd / A) as a function of the brightness, calculated from current-voltage-brightness characteristics (IUL characteristics), and the lifetime are determined.

Table 2 summarizes the results of the device measurement. The electroluminescent devices comprising the compounds according to the invention show an increased lifetime with improved efficiency.

Table 2: Device results with spiro-ketone as host material and with lr (piq) ₃ or compounds according to the invention as dopant

Claims

claims

1. Compound of general formula I.

Formula I

or the general formula (II)

Formula Il

in which

M is a metal ion of oxidation state +2,

Ar is the same or different at each occurrence an aromatic or heteroaromatic ring system which may be substituted by one or more arbitrary radicals R and the ring systems Ar may optionally be linked together by single bonds or any radicals R, Y is the same or different at each occurrence C, N or P, with the proviso that always two C atoms and two N atoms or always two C atoms and two P atoms are bound to the metal,

R ^{1 is} any residue.

2. Compounds according to claim 1, wherein:

R is the same or different at each occurrence H, D, F, Cl, Br, I, N (Ar ¹ ) ₂ , N (R ² ) ₂ , CN, NO ₂ , Si (R ² ) ₃ , B (OR ² ) ₂ , C (= O) Ar ¹ , C (= O) R ² , P (= O) (Ar ¹ ) ₂ , P (= O) (R ² ) ₂ , S (= O) Ar ¹ , S (= O) R ² , S (= O) ₂ Ar ¹ , S (= O) ₂ R ² _, -CR ² = CR ² Ar ¹ , OSO ₂ R ² , a straight-chain alkyl, alkoxy or

Thioalkoxygruppe having 1 to 40 carbon atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 carbon atoms, which may be substituted in each case with one or more radicals R ² , wherein one or more non-adjacent CH ₂ Groups by R ² C =CR ² , C≡C, Si (R ² ) ₂₎ Ge (R ² ) ₂ , Sn (R ² ) ₂ ,

C = O, C = S, C = Se, C = NR ² , P (= O) (R ² ), SO, SO ₂ , NR ² , O, S or CONR ² may be replaced and wherein one or more H Atoms can be replaced by D, F, Cl, Br, I, CN or NO ₂ , or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, each by one or more

Radicals R ² may be substituted, or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R ² , or a combination of these systems, wherein two or more substituents R also together can form a mono- or polycyclic, aliphatic or aromatic ring system, Ar ^{1 is} identical or different at each occurrence, an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, which may be substituted by one or more non-aromatic radicals R,

R ¹ is identical or different at each occurrence with H, D, F, CF ₃ , CN, an alkyl, alkoxy or thioalkoxy group having 1 to 40 carbon atoms or a branched or cyclic alkyl, alkoxy or thio alkoxy group with From 3 to 40 C atoms, each of which may be substituted with one or more R ² radicals, one or more non-adjacent CH ₂ groups represented by R ² C = CR ² , C≡C, Si (R ² ) ₂ , Ge (R ² ) 2, Sn (R ² ) ₂ , and wherein one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO ₂ , or an aromatic or heteroaromatic ring system with 5 to 60 aromatic ring atoms, each of which may be substituted by one or more radicals R ² , or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R ² , or a combination of these systems, where R ^{1 can} also form with R a mono- or polycyclic, aliphatic or aromatic ring system,

R ² is the same or different at each occurrence H, D, F, CN or an aliphatic, aromatic and / or heteroaromatic

Hydrocarbon radical having 1 to 20 carbon atoms, in which also one or more H atoms may be replaced by F, wherein two or more substituents R ² also together form a mono- or polycyclic, aliphatic or aromatic ring system.

3. Compounds according to claim 1 or 2, characterized in that M is Pt or Pd, in particular Pt.

4. Compounds according to one or more of claims 1 to 3, wherein the following applies: M is Pt,

Ar is the same or different at each occurrence, an aromatic or heteroaromatic ring system having from 5 to 10 aromatic

Ring atoms, which can be substituted by several radicals R,

Y is the same or different at each occurrence of C or N, with the proviso that always two C atoms and two N atoms to the

Metal are bound

R is the same or different at each occurrence H, N (Ar ¹ ) ₂ , CN, a straight-chain alkyl group having 1 to 10 carbon atoms, or an aromatic or heteroaromatic ring system having 5 to 15 aromatic ring atoms, each by one or more radicals R ² may be substituted,

R ¹ is identical or different at each occurrence H, D, CN, an alkyl group having 1 to 3 carbon atoms, or an aromatic or heteroaromatic ring system having 5 to 10 aromatic ring atoms, each being substituted by one or more R radicals can

R ² is identical or different at each occurrence, is H, F, CN or an aliphatic, aromatic and / or heteroaromatic hydrocarbon radical having 1 to 20 C atoms, where two or more substituents R ^{2 are} also together with one another mono- or polycyclic, can form aliphatic or aromatic ring system; and

Ar ¹ is as defined in claim 2.

5. Compounds according to one or more of claims 1 to 4, characterized in that Ar is selected from benzene,

Naphthalene, pyridine, pyrimidine, pyrazine, pyridazine, quinoline, isoquinoline, Furan, thiophene, pyrrole, benzofuran, benzothiophene and indole, most preferably benzene, naphthalene, pyridine, quinoline and isoquinoline.

6. Compounds according to one or more of claims 1 to 5 according to the formulas III or IV,

Formula Formula IV

wherein M, Y, R and R1 have the meaning given in claims 1 and 2 and X is CR or N.

7. Compounds according to claim 6, characterized in that a maximum of two symbols X per cycle for N and the other symbols X are in this cycle for CR.

8. Compounds according to one or more of claims 1 to 7 according to one of the formulas V to XVI:

Formula VI Formula.VII

Formula V

Formula VIII Formula IX Formula X

Formula XIII

Formula XVI

Formula XIV Formula XV

wherein the symbols used have the meanings given in claims 1, 2 and 6.

9. Oligomers, polymers or dendrimers containing one or more compounds according to one or more of claims 1 to 8, wherein one or more bonds of the compounds of formula I or II to the polymer, oligomer or dendrimer are present.

10. A process for the preparation of the compound according to one or more of claims 1 to 8, characterized in that the free ligand is reacted with a corresponding metal salt to the complex.

11. Use of compounds according to one or more of claims 1 to 9 in an electronic device, in particular in organic electroluminescent devices (OLEDs) or polymeric electroluminescent devices (PLEDs), organic integrated circuits (O-ICs), organic field-effect transistors

(O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic solar cells (O-SCs), organic optical detectors, organic photoreceptors, organic field quench devices (O-FQDs), light-emitting electrochemical cells (LECs) or organic

Laser diodes (O-laser).

12. A layer comprising one or more of the compounds according to one or more of claims 1 to 9.

13. Electronic device, in particular organic electroluminescent devices or polymeric electroluminescent devices (OLEDs, PLEDs), organic integrated circuits (O-ICs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light emitting transistors

(O-LETs), organic solar cells (O-SCs), organic optical detectors, organic photoreceptors, organic field quench devices (O-FQDs), light-emitting electrochemical cells (LECs) or organic laser diodes (O-lasers) containing one or several compounds according to one or more of claims 1 to 9.

14. Organic electroluminescent device according to claim 13, characterized in that the compound according to one or more of claims 1 to 9 as an emitting compound in an emitting layer or as a charge transport compound in a

Charge transport or charge injection layer is used.